The main aspects concerning the use of the young stems and fruits of the prickly pear cactus (Opuntia spp.) into human food are discussed. Topics considered include an overview of the prickly pear ecological characteristics, the biochemical composition of the cladodes and fruits, their postharvest behavior, and the possibilities of their industrial transformation and conservation. The food potential for all parts of the fruits and stems are reviewed. The prickly pears are a group of cactus species adapted to semiarid conditions and native to the American continent. Owing to crassulacean acid metabolism, these plants show a high water-use efficiency, they have a high relatively potential of biomass production, and they are extremely drought tolerant. Their fruits are highly regarded and consumed around the world. The tender young pads are an important part of the food in Mexico and in southern United States, and the mature cladodes are used as animal fodder.